LEGLESS LIZARDS 



THE SLOW-WORM AND THE AMPHISBJENA 

 This homely little creature will serve as a type of 

 those numerous lizards which have deserted the straight 

 road of reptilian development, and gone and lost their 

 legs as if they were mere snakes. It is seldom that the 

 Reptile House is without the slow- worm or blind-worm as 

 it is usually called ; it must be remembered that in 

 terming it a worm nothing contemptuous or even 

 wormy in the ordinary sense of the word is intended 

 or implied ; the word worm is good Scandinavian for 

 snake, and the name thus perpetrates a zoological 

 error of a lesser kind. Why the worm under debate 

 is not a snake is a question that many would find it 

 hard to answer. And why " blind " is a further question 

 much to the point. The blindness is here with the 

 observer who first gave it the name and not with the 

 lizard. It has good, even particularly good, eyes, sharp 

 in their outlook, and provided, as are the eyes of nearly 

 all lizards, with movable lids. Here, then, is the first 

 reason why the Anguis fagilis is not a snake ; for no 

 snake has eyelids. If the slow- worm be fed it will be 

 noted that it eats in the usual lacertilian fashion, and 

 does not divaricate its distensile jaws, getting outside 

 its food as a snake does ; in fact the two lower jaws 

 where they meet are firmly united and not merely j oined 

 by a lax ligament as they are in all except a very few 

 kinds of snakes. Other and satisfying reasons for 

 placing the slow-worm among lizards can be seen only 

 after an anatomical examination. Snake-like lizards 

 have at least vestiges of limbs, which are completely 

 wanting among snakes except the merest traces in 

 some few forms, the boas and their immediate allies. 

 No snake has a breast bone or sternum. These are 

 some of the reasons there are plenty of others why 

 the slow-worm is a lizard and not a snake. The slow- 

 worm is perhaps the commonest of British reptiles. But 



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